Stoker



April 26, 1938. C, C, K|RBY A 2,115,464

' sToKER FiledAug. 15, 1934 's sheets-sheet 1f APHl 25, 1938- I c. c.KIRBY 2,115,464

y i STOKER i Filved Aug. 15., 1934 3 Sheets-Sheet 2 C. C. KIRBY,

April 26, 1938.

STOKERv Filed Aug'. 15, 1934- 5 Sheets-Sheet 3 Patented Apr. 26, 1938UN11ED STATES PATErVr- OFFICE s'roxEa ohm-les c. Kirby, Decatm n1.Appncmn August 15, 1934, serial No. '139,848

3 claims. (o1. 11o-115) and measured output of fuel which is fed intothe fire bed of the furnace.

Another important object of the invention is the provision of a novel,simple and highly eilicient means vfor distributing the fuel in an evenand uniform layer over the;k entire flre box area, thus accomplishingmore complete and emcient combustion of the fuel in the furnace.

A further important object of the invention is the provision of a stokerwhich is built into a completeportable unit, and'which may be cheaplymanufactured to perform its operations in a positive and effectivemanner.

A further important object of the invention is the provision in a Stokerof mechanism for manually varying the amount of fuel delivered'by thestoker into the furnace in an amount proportionate to the size of thefire box in the furnace;

A still further object of the invention is the provision of means forautomatically restraining the delivery of fuel after a predeterminedamount has been fed into the re box,'4 and for automatically releasingsaid means to start a new delivery of fuel.

Another object of the invention is the provision of means whereby thefuel delivered into the re box of the furnace will be maintained below apredetermined size.

Numerous other objects and advantagftscf'the:

Figure 1 is a side view of the stoker embodying my present inventionconnected to a furnace and showing the hopper, screw conveyer, anddistribution chamber in section; l

Fig. 2 is a horizontal section taken substantially on'the line 2-2 ofFig. 1;

Fig. 3 is a fragmentary enlarged sectional view of a portion of thehopper and screw conveyer and shows the adjustable feed controlmechanism;

Fig. 4 is a section taken substantially on the line 4 4 of Fig. 3;

Fig. 5 is a fragmentary .view showing a portion of the feedcontrolmechanism in a different position from that shown in Fig. 3;

Fig. 6 is a perspective View of the distribution chamber;

Fig. 7 is a perspective view of the distribution disk;

end a lid or closure II, front and side walls I2 la notch or aperture 22to provide an exit for the 126, is adapted to rotate within the conveyertube I 8 and extends to practically the full length there- Fig. 8 is aperspective view showing the screw conveyer insert for preventingoversize lumps of fuel from entering the conveyer screw;

Fig. 9 is a plan view of a modified form of distribution disk; and 5Fig. 10 is a wiring diagram of the circuit for automatically operatingthe Stoker.

Referring to the drawings, the stoker is shown comprising a storagehopper I Il having at its upper 10 sloping inwardly from top to bottomto form a trough-shaped portion I3 at its lowest extremitlr and a.vertically disposed rear wall.

The trough portion I3 may be welded or otherwise secured by an angleband I4 to effect a sealed 15 closure with a member I5 of tubular formhaving teeth I6 along the upper edge and along one of the vertical edgesof an aperture I1, the teeth I6 serving to break up any unduly largelumps of fuel which may have entered the hopper. 20

The member I5 is adapted to embrace a vertically disposed screw conveyertube I8, which is provided at its lower end with a notch or aperture I9corresponding in height to the trough I3 and is cut back in depth to itsaxis as shown at 25 20, to allow for the entrance of the fuel. Adjacentand below the aperture I 3 the tube I8 is rigidly mounted in anydesiredmanner on the frame or housing of a gear reducer 2|.

The conveyer tube I8 has at its uppermost end fuel into av distributionchamber housing, generally designated by reference character`23.

3A screw conveyer 25, fixed to a driven shaft of, i. e. from the base ofthe trough I3 to theV lower end of the` upper aperture 22. Adjacent thelower portion of this screw 25 is a cup-shaped closure member 2l whichis adapted to snugly embrace the inner wall of the tube I8 and the shaft26, thus preventing any escape of dust or foreign matter into themechanism directly below, as will be later described.

The screw 25 has at its upper end a paddleshaped member 28 inregistration with the notch 22 and adapted to be xedly held on theconveyer shaft 26 so that the screw and paddle. will rotate in unison. lA

Referring'now to Fig. 1, the gear reducer 2l is fastened rigidly bymeans 3| to a rectangularshaped base or support member 32 having casters33 which may either be xedly or swivelly mounted, the base member alsoserving to support the storage hopper through supports 34.

Referring now` to the main drive mechanism, I

have provided a motor 35 vertically disposed and spaced apart from theconveyer tube I8 having bearing at its'- lower end at 36 on the frame ofside portions 4| and a horizontal base portion 42 which is formed with afiange portion 43 to enclose the tube I8. The distribution chamberterminates in an opening 44 which is adapted to -abut a door 45 of afurnace 46, this door having an opening 41 of width and length to matchthe opening 44. To preclude leakage of dust, etc., during the operationofthe stoker, an angle iron strip or other suitable means 41' is or maybe weldedl around the periphery of the opening 44- to abut against thedoor 45.

It will be noted that :the outwardly flaring sides 4| of thedistribution chamber (Fig. 1) have a top horizontal edge 48, anddownwardly sloping edges 49, continuing into a horizontal edge 50 whichterminates at the furnace door 45. A cover plate 5|, whose surfaceconforms to and rests upon the edges of the distribution chamber,

serves asan enclosure for this chamber. A removable plate 52, held inplace by means 53 above the opening 44, is provided for the purpose ofobserving the condition of the fire box from time to time as desired.

Referring now to the portion of the conveyer tube immediately below theaperture 22, an inclined guide chute 55 is formed and fastened to thetube at 56. 'I'he chute extends downwardly to within a normal workingdistance of the dis' tributor disk 39 and in its extension maypreferably be, arcuate in form. A deflector bar 58 is pivoted at 59 tothe lower end of the guide chute 55.

The distributor disk 39 comprises a rotating` circular disk 6| having aplurality of blades 62 fastened to its upper 'surface by bolts 63, orother suitable fasteningA means. The blades 62 may be of angle iron formand, as will be seen from Figs. 2, 7, and 9, are placed with theiroutermost ends 64 diametrically opposite one another and inclose-proximity to the periphery of the rotating disk. These bladesextend along the surface of the disk with their vertical planes lying oneither side of its axis and equidlstant therefrom. The' blades areparallel to. one another and terminate at 65 just before reaching thecenter of the disk. Slots 66 are or may be provided for angularadjustment of the blades if desired (see Fig. 9)..

'I'he distributor disk is rigidly secured to the upper extension of themotor drive shaft 31 by suitable means 61. Referring to Fig. 1 it willbe apparent that the distributor disk assembly is positioned in closeproximity to the base of the distribution chamber housing 23, whichobviates the danger of pieces of fuel or foreign matter vlodging beneaththe distributor disk. A housing 68 is provided for protection from therotat- "means, a brief explanation of the operation of the parts thusfar described may serve to more clearly disclose .the invention.Assuming that the circuit for 'the motor is closed, rotation of themotor shaft which normally runs at 1750 R. P. M.-

will, through the gear reducer, rotate the conas the invention is laterdescribed. Fuel will be fed up the screw and to the paddle-likestructure which tends to prevent any crowding of the fuel, the fuel thendropping by its own weight down the inclined chute and onto the rotatingdistributor disk. The staggered blades on the disk tend to hurl thepieces of fuel through the opening in the fuel door of the furnace'andinto the lire box chamber. This operation continues until automaticallystopped'.

The mechanism for accomplishing this automatic stopping (Figs. 3 to5)"comprises a ratchet wheel 15, pinned at 16 to a horizontallydisposed. shaft 11 having bearing at 18 in a support o-r bracket 19which in turn is rigidly secured at to the gear reducer housing 2|.

Fastened to the support 19 atl 8|-and vertically disposed relativethereto is a second support 82 having a horizontal bearing 83 adapted toreceive an adjustable tubular sleeve 84, the inner or rearward end ofwhich extends through an opening in the conveyer tube below thecuplforward end and being secured at its rearward end to the rod 81 inany desired manner.

The reciprocating rod 81 has a correspondingly reduced portion 89 whichextends from the shoulder 88 beyond the end of the tubular sleeve toabut against an eccentric 9| which'may be pinned or otherwise fastenedto the screw conveyer shaft at 92. 'Ihis rod extends beyond the springhousing member and is provided with a flattened portion having a pivot93 for a connector link 94 in turn loosely pivoted 'at 95 to a lever orarm 96. The lever or arm is loosely' mounted on the shaft 11 and isprovided with a ratchet dog or pawl 91 adapted to drive the ratchetwheel in a counter clockwise direction, viewing Figs. 3 and 5.

Also mounted on the ratchet wheel shaft 11 opposite thel ratchet wheeland adjacent the bracket 19 is an arm 98 rigidly fixed to the shaft 11at 99 and pivoted at |00 to a connecting link IUI. The link I0| is`pivoted toan arm |02, fixed to a stub shaft |03 adapted to operate aswitch |2|, to be described hereafter, within a housing |04.

Referring to the support 82, it will be noted that an extension |05 isprovided, extending above and forming a part of the horizontal bearing83 in the support. 'Ihis extension |05 is provided with an opening |06adapted to receive a plunger |01 having a knurled head |08 at its upperend and a conical-shaped member |09 at its inner end. The conical member|09 is normally urged into any one of a series of corresponding conicalopenings ||0 by a spring I within an enlargement of the opening |06. Theopenings ||0 are located in the upper surface of the adjustable tubularsleeve 84, and a key and keyway (not shown) prevents the tubular sleevefrom rotation about its axis and consequent misalinement of the openings||0 .with the plunger.

- away from the shoulder v88 in the sleeve 84.

Motion is thus imparted to the arm 95 which, through its pawl 91,rotates the-ratchet wheel 15 through a portion of its circumference,after which the spring 85 urges the mechanism to its original positionas shown in Fig. 3. The motion of the ratchet wheel, which is fixed tothe shaft, imparts a corresponding degree of motion to the linkage andto the switch. A complete revolution of the ratchet wheel serves tooscillate the switch operating shaft from an open to a closed positionand back to open position. To prevent any but a uni-directional motionof the ratchet wheel a gravity held latching dog HZ is provided, whichis pivoted at ||3 in the ratchet shaft support 19. It will be apparentthat the longest possible stroke vof the rod 31 and pawl 91, which wouldcorrespond tothe complete throw of the eccentric 9|, will impart acomplete revolution to the ratchet wheel 15 in the shortest possibletime, and this may be interpreted as the minimum time for deing, itbeing understood that any number of adjustments may be incorporatedwithout changing any ofv the desirable features.

The mechanism just described is illustrated in Fig. 5 and it will beapparent that in the new adjustment therein shown the entire ratchetdriving assembly will be drawn forwardly or outwardlyv leaving a gapbetween the end of the reduced portion 89 and the engaging surface ofthe eccentric 9|. In. this manner the distance travelled by the ratchetwheel for each revolution of the eccentric will be lessened,necessitating a larger number of revolutions for the screw conveyershaft to complete one revolution of the ratchet.

wheel, which constitutes a complete cycle of operation. Moving theplunger into still another notch will again vary the time of a completecycle.

It will be apparent that this mechanism may be operatedeffectively by anunskilled operator and that it provides for a series of adjustments intothe distribution chamber where it falls normally by its own weight ontothe rapidly whirling distributor disk, the blades on the distributordisk carry the fuel with it and the centrifugal forces tend to throw thefuel away from the whirling disk and into the furnace As the fuel leavesthe guide chute it will contact or strike the blades at,

different points along their presented faces thus varying their angulardirections on leaving the The fuel is thus directed into the furnace.ina plurality of varying` angular directions until YeIyfPOrtion of thearea of the fire box is covered i ith a; uniform and evenly distributedlayer.

u' l,Spreading a layergf fuel on a fire bed in this manner causes amorey even and intense distribution of heat within the combustionchamber and enables steam to be generated in a much shorter time than isrequired in the methodsI now employed where the fuel is either heaped orbanked in the fuel box. y

Exhaustive tests have shown that preparing the rebox in the mannerhereinbefore described has resulted in greater efficiency in theoperation of the furnace with a much i'lner ash deposit and lessclinkers than has heretofore been possible. It has also been found thatplacing the motor in the position illustrated on the drawings has servedto keep it cool, a factor which is most important in the upkeep of themachine.

The invention is also intended for automatic operation and to this endFig. 10 discloses a wiring diagram in which leads ||1 and 8 maybeconnected to any'electric outlet to operate the motor 35. A switch |2|,connected in parallel with other switches in the circuit, is the switchreferred to above as being within the housing |04 and oscillated by thelinkage of the ratchet wheel mechanism previously described and closesthe circuit through contact with the segment |22.l

When the ratchet wheel mechanism has completed its cycle of operationthe -switch is thrown into an open circuit position, as shown in brokenlines in this figure. A thermostatic switch |23, connectedin series withthe motor 35 and in parallel with the switch |2|, may be used to closethe circuit to the motor when the temperature at any desired controlpoint in the heating system falls below a predetermined point. When thistakes place the stoker will operate through another complete cycle andbe stopped, unless the thermostatic switch is still closed, which willautomatically initiate another complete cycle of operation. These twoswitches will automatically control the operation of the stoker withoutany attention except for the replenishing of fuel to the hopper.

A third and manually operated switch |25 may be employed to initiallystart the device into operation, and this switch is held in a normallyinoperative position by a spring |26. 'Ihis switch |25 may be mountedon-or within the housing' |04 for convenience, if desired, as shownginFig. 3. In its initial operation, the switch |25 is urged into a closedcircuit position, the operator holding the switch in this positionmomentarily until vthe switch |2| acts to close the circuit to themotor, after which the switch |25 is released., It is apparent that afull automatic switching arrangement might be provided, the form shownon the drawings being merely a preferred arrangement and forms no partof the present invention.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent4 .ber, a hopper, extending to a point below the chargingchamber, a screw conveyor arranged to convey fuel upward from saidhopper to said charging chamber, means inthe charging chamber directingthe fuel to the impeller, a motor below said impeller, a shaftsubstantially parallel to said conveyor extending vertically from saidmotor and operatively engaging said impellerl operatively engaging saidimpeller and said motor, and means operatively connecting said motor andsaid conveyor, said means being so constructed and arranged as to x therelative speeds of said conveyor and said impeller at a predeterminedratio.

3. In a furnace stoklng mechanism a charging chamber having a dischargeoutlet adapted to communicate with a furnace, a rotary impeller in saidchamber, a hopper extending to a point below *the charging chamber, ascrew conveyor arranged to convey fuel upward from said hopper to saidcharging chamber, means in the charging chamber directing the fuel tothe impeller, a

motor below said impeller, a-shaft substantially parallel to said screwconveyor extending upward from said motor and operatively engaging saidimpeller and motor, and means operatively connecting said motor and saidconveyor.

CHARLES C. KIRBY.

